Alert archive / Virginia / Tornado Watches in 2002

Tornado Watch 172

April 28, 20029 counties in Maryland; 72 counties in Virginia; 6 counties in West Virginia

The Storm Prediction Center issued this tornado watch at Apr 28, 2002, 3:30 PM EDT for 9 counties in Maryland; 72 counties in Virginia; 6 counties in West Virginia. It was in force for 6 hr.

The area

The outline as issued.

The facts

Issued
Apr 28, 2002, 3:30 PM EDT (19:30 UTC)
Expired
Apr 28, 2002, 9:00 PM EDT
In force
6 hr
Issued by
the Storm Prediction Center
All 87 counties

Baltimore County, MD, Carroll County, MD, City of Baltimore, MD, Frederick County, MD, Harford County, MD, Howard County, MD, Montgomery County, MD, Prince George's County, MD, Washington County, MD, Albemarle County, VA, Alleghany County, VA, Amherst County, VA, Appomattox County, VA, Arlington County, VA, Augusta County, VA, Bath County, VA, Bedford County, VA, Botetourt County, VA, Buckingham County, VA, Campbell County, VA, Carroll County, VA, Charlotte County, VA, City of Alexandria, VA, City of Buena Vista, VA, City of Charlottesville, VA, City of Covington, VA, City of Danville, VA, City of Fairfax, VA, City of Falls Church, VA, City of Fredericksburg, VA, City of Galax, VA, City of Harrisonburg, VA, City of Lexington, VA, City of Lynchburg, VA, City of Manassas, VA, City of Manassas Park, VA, City of Martinsville, VA, City of Radford, VA, City of Roanoke, VA, City of Salem, VA, City of Staunton, VA, City of Waynesboro, VA, City of Winchester, VA, Clarke County, VA, Craig County, VA, Culpeper County, VA, Cumberland County, VA, Fairfax County, VA, Fauquier County, VA, Floyd County, VA, Fluvanna County, VA, Franklin County, VA, Frederick County, VA, Giles County, VA, Goochland County, VA, Grayson County, VA, Greene County, VA, Halifax County, VA, Henry County, VA, Highland County, VA, Loudoun County, VA, Louisa County, VA, Madison County, VA, Montgomery County, VA, Nelson County, VA, Orange County, VA, Page County, VA, Patrick County, VA, Pittsylvania County, VA, Prince Edward County, VA, Prince William County, VA, Pulaski County, VA, Rappahannock County, VA, Roanoke County, VA, Rockbridge County, VA, Rockingham County, VA, Shenandoah County, VA, Spotsylvania County, VA, Stafford County, VA, Warren County, VA, Wythe County, VA, Berkeley County, WV, Hampshire County, WV, Hardy County, WV, Jefferson County, WV, Morgan County, WV, Pendleton County, WV

The radar

The Roanoke radar (KFCX), 125 km from the middle of the area, began a volume at 19:29 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

Warnings issued inside it

30 tornado, severe thunderstorm and flash flood warnings for its counties while it was in force.

IssuedProductOfficeCountiesLasted
Apr 28, 3:43 PM EDTSevere Thunderstorm WarningRNKCraig, Giles47 min
Apr 28, 3:53 PM EDTSevere Thunderstorm WarningRNKBotetourt22 min
Apr 28, 4:05 PM EDTSevere Thunderstorm WarningRNKBedford40 min
Apr 28, 4:05 PM EDTSevere Thunderstorm WarningLWXGrant, Hardy40 min
Apr 28, 4:11 PM EDTSevere Thunderstorm WarningRNKRoanoke, City of Roanoke, City of Salem49 min
Apr 28, 4:38 PM EDTTornado WarningLWXRockingham, Shenandoah22 min
Apr 28, 4:41 PM EDTSevere Thunderstorm WarningRNKWythe49 min
Apr 28, 4:47 PM EDTTornado WarningRNKBedford, Campbell, City of Lynchburg28 min
Apr 28, 4:59 PM EDTSevere Thunderstorm WarningLWXPage, Rappahannock, Shenandoah46 min
Apr 28, 5:13 PM EDTSevere Thunderstorm WarningRNKAppomattox47 min
Apr 28, 5:18 PM EDTSevere Thunderstorm WarningLWXGrant, Hardy42 min
Apr 28, 5:20 PM EDTSevere Thunderstorm WarningRNKFranklin25 min
Apr 28, 5:27 PM EDTSevere Thunderstorm WarningRNKCampbell48 min
Apr 28, 5:30 PM EDTSevere Thunderstorm WarningRNKCharlotte30 min
Apr 28, 5:34 PM EDTSevere Thunderstorm WarningRNKBedford26 min
Apr 28, 5:44 PM EDTSevere Thunderstorm WarningRNKPittsylvania46 min
Apr 28, 5:48 PM EDTTornado WarningLWXCulpeper, Fauquier, Rappahannock27 min
Apr 28, 5:50 PM EDTSevere Thunderstorm WarningRNKHenry, City of Martinsville25 min
Apr 28, 5:57 PM EDTSevere Thunderstorm WarningRNKCharlotte33 min
Apr 28, 6:04 PM EDTTornado WarningRNKHalifax, Pittsylvania26 min
Apr 28, 6:13 PM EDTTornado WarningLWXFairfax, Fauquier, Prince William, City of Manassas32 min
Apr 28, 6:13 PM EDTSevere Thunderstorm WarningRNKPittsylvania, City of Danville47 min
Apr 28, 6:27 PM EDTTornado WarningRNKCharlotte, Halifax33 min
Apr 28, 6:48 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Calvert, Charles, Prince George's42 min
Apr 28, 6:59 PM EDTSevere Thunderstorm WarningLWXAnne Arundel, Howard, Montgomery46 min
Apr 28, 7:02 PM EDTTornado WarningLWXCalvert, Charles, Prince George's, Saint Mary's43 min
Apr 28, 7:51 PM EDTSevere Thunderstorm WarningRNKPulaski39 min
Apr 28, 8:14 PM EDTSevere Thunderstorm WarningRNKFloyd46 min
Apr 28, 8:17 PM EDTSevere Thunderstorm WarningRNKFloyd28 min
Apr 28, 8:22 PM EDTSevere Thunderstorm WarningRNKMontgomery23 min

The nearest sounding before it

Roanoke, VA (KRNK), launched 12:00Z, 7.5 hours before the alert went out and 70 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.

Skew-T log-pSkew-T log-p diagram, Roanoke, VA at 12:00Z on 2002-04-28Temperature and dew point through the depth of the atmosphere, with the mixed-layer parcel. CAPE 17 joules per kilogram.LCLLFCEL10008507005003002001001 km2 km3 km6 km9 km12 km15 km-30°-20°-10°0°10°20°30°40°
Temperature in red, dew point in green, the mixed-layer parcel dashed.
HodographHodograph, Roanoke, VA at 12:00Z on 2002-04-28The wind through the lowest 10 kilometers. Zero to 1 km storm-relative helicity 370 square meters per square second.19395878Sfc1 km3 km6 km9 kmRMLM
The wind turning with height, colored by layer: ground to 1 km, 1 to 3 km, 3 to 6 km, 6 to 10 km.
Mixed-layer CAPE
17 J/kg
Mixed-layer CIN
-448 J/kg
Mixed-layer LCL
642 m above ground
0-6 km bulk shear
54 kt
0-1 km storm-relative helicity
370 m²/s²
0-3 km storm-relative helicity
435 m²/s²
Significant tornado parameter
0.0
Supercell composite
0.0

Open this sounding in Storm Lab

The text

As transmitted, in the capitals the NWS used until 2016.

000
WWUS20 KWNS 281912
SEL2  
SPC WW 281905
DCZ000-MDZ000-VAZ000-WVZ000-290100-

URGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 172
STORM PREDICTION CENTER NORMAN OK
305 PM EDT SUN APR 28 2002

THE STORM PREDICTION CENTER HAS ISSUED A
TORNADO WATCH FOR PORTIONS OF

   DISTRICT OF COLUMBIA
   MARYLAND                           
   CENTRAL AND WESTERN VIRGINIA                           
   EASTERN PANHANDLE OF WEST VIRGINIA         

EFFECTIVE THIS SUNDAY AFTERNOON AND EVENING FROM 330 PM UNTIL 900
PM EDT.

TORNADOES...HAIL TO 2 INCHES IN DIAMETER...THUNDERSTORM WIND GUSTS
TO 70 MPH...AND DANGEROUS LIGHTNING ARE POSSIBLE IN THESE AREAS.

THE TORNADO WATCH AREA IS ALONG AND 70 STATUTE MILES EAST AND WEST
OF A LINE FROM 45 MILES WEST OF DANVILLE VIRGINIA TO 45 MILES
NORTHWEST OF BALTIMORE MARYLAND.

REMEMBER...A TORNADO WATCH MEANS CONDITIONS ARE FAVORABLE FOR
TORNADOES AND SEVERE THUNDERSTORMS IN AND CLOSE TO THE WATCH AREA. 
PERSONS IN THESE AREAS SHOULD BE ON THE LOOKOUT FOR THREATENING
WEATHER CONDITIONS AND LISTEN FOR LATER STATEMENTS AND POSSIBLE
WARNINGS.

OTHER WATCH INFORMATION...  CONTINUE...WW 166...WW 167...WW
168...WW 169...WW 170...WW 171

DISCUSSION...AS UPPER LEVEL SHORTWAVE TROUGH APPROACHES THE
AREA...STORMS ARE EXPECTED TO DEVELOP EAST OF THE APPALACHIANS.
MORE HEATING WILL RESULT IN WEAK-MODERATE INSTABILITY. THIS
INSTABILITY WITH STRONG SPEED SHEAR AND LOW LEVEL VEERING IS
SUFFICIENT FOR SUPERCELLS WITH LARGE HAIL/DAMAGING WINDS AND A FEW
TORNADOES. 

AVIATION...TORNADOES AND A FEW SEVERE THUNDERSTORMS WITH HAIL
SURFACE AND ALOFT TO 2 INCHES.  EXTREME TURBULENCE AND SURFACE WIND
GUSTS TO 60 KNOTS.  A FEW CUMULONIMBI WITH MAXIMUM TOPS TO 450. 
MEAN STORM MOTION VECTOR 26040.

...IMY

393,0755 363,0785 363,0812 393,0783

SPC that day

Everything else SPC issued on the same UTC day.

IssuedProductOfficeCountiesLasted
Apr 28, 1:30 PM EDTTornado WatchSPCAllegany, Garrett4 hr
Apr 28, 5:00 PM EDTSevere Thunderstorm WatchSPCAllegany, Garrett4 hr
Apr 28, 5:00 PM EDTSevere Thunderstorm WatchSPCAllegany, Garrett4 hr
Apr 28, 6:00 PM EDTTornado WatchSPCCalvert, Caroline, Cecil, Dorchester, Kent, Queen Anne's and 5 more4 hr
Apr 28, 2:15 PM EDTTornado WatchSPCCity of Bristol5 hr
Apr 28, 6:45 PM EDTTornado WatchSPCCity of Danville3 hr
Apr 28, 11:45 AM EDTTornado WatchSPCBrooke, Hancock, Jackson, Mason, Ohio, Pleasants and 2 more5 hr
Apr 28, 12:30 PM EDTTornado WatchSPCCabell, Kanawha, Lincoln, Putnam, Wayne5 hr
Apr 28, 2:30 PM EDTTornado WatchSPCMarshall6 hr

Nearby

Tornado Watches in Virginia, 2002Tornado Watches in Maryland, 2002Tornado Watches in West Virginia, 2002Every tornado watch in 2002

Sources

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.